Well, I'm stumped. Spoilersss.

[Karn]

All right, I've gone back to try and collect all the treasures and I seem to be stuck at a blockage inside the whale.

I'm in a room with an octopus and the pearl that I need, however it's blocked by a door and I can't figure out what to do.

The octopus sings four notes and I count five on the lamps outside.

Singing the odd note out won't work, trying to add it into the melody won't work...

Am I missing something, here? I really want what's through that door north of the whale.

[Don Andy]

All right, I've gone back to try and collect all the treasures and I seem to be stuck at a blockage inside the whale.

I'm in a room with an octopus and the pearl that I need, however it's blocked by a door and I can't figure out what to do.

The octopus sings four notes and I count five on the lamps outside.

Singing the odd note out won't work, trying to add it into the melody won't work...

Am I missing something, here? I really want what's through that door north of the whale.

The octopus sings four colours in a certain order. The lanterns outside can be lit up with the Sun form (charge and release) and each glows in another colour. Figure out the rest :p

[Karn]

I totally blanked out on that, can't believe I got stuck on such a simple puzzle. Figured it out pretty easy after you mentioned the order.